


Menstruation

by Cassie_Bones



Category: Supergirl (TV 2015)
Genre: Gen, I'm not Kryptonian, Kara learns about menstruation, Playtex commercials are bogus, also we learn a little bit about Kryptonian anatomy, it's a lot of fun, precious cinnamon roll, so don't take my word for this, sort of, too good for this world, too pure
Language: English
Status: Completed
Published: 2017-02-13
Updated: 2017-02-13
Packaged: 2018-09-24 03:55:34
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,274
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/9699377
Author URL: https://archiveofourown.org/users/Cassie_Bones/pseuds/Cassie_Bones
Summary: When Kara Zor-El Danvers first learns about menstruation, she's shocked.





	

**Author's Note:**

> I had a question. Posted it on Tumblr. 300+ notes later...

Based on [THIS POST](http://cassiebones.tumblr.com/post/157200109257/does-kara-have-a-period-i-mean-i-dont-know-how) on Tumblr. Feel free to join the discourse.

* * *

 

When Kara Zor-El Danvers first learns about menstruation, she’s shocked.

Because for an entire _week_ out of every month (which is between 28 and 31 days here on Earth), humans who have an organ called a ‘ _uterus_ ’ are in constant pain. The majority of people on Earth with these organs are female, Kara learns in health class, and they are expected to go through their daily routines while their organs shed blood and contract painfully throughout the day.

This is something Kara doesn’t quite understand, but she doesn’t ask any questions in class, lest she raise suspicions about her race. Instead, she jots down questions to ask her adoptive family later. Meanwhile, she continues to listen to her teacher as she spells out all the other side effects of a ‘period’ (Kara is certain that she learned about periods in English class, but maybe they’re more complicated than she had first assumed).

These side effects include:

  * bloating, which means that the afflicted person’s body expands slightly and makes it harder to wear their normal attire.
  * migraines, which cause pain to the cranium and make it difficult for afflicted persons to process light and sound, as they become more sensitive to them.
  * mood shifts, which are caused by the decrease in estrogen in an afflicted person’s body.
  * vaginal bleeding, which sounds bloody unpleasant and very unhealthy to Kara. No creature should bleed that much over the course of a weak. How do humans live through that?
  * and fatigue; probably from all the blood loss.



All of that in addition to cramping makes Kara begin to appreciate her fellow classmates a little bit more and she finds herself wondering which of them is currently ‘on their period’ as she’s heard them say. She also begins to wonder if _she_ should be on her period, as well. Humans are supposed to menstruate and she is a female on this earth; isn’t she expected to have one of those uterus things?

When she gets home that first day, she finds Alex in her room, laying on her bed and reading a biology textbook. The door is cracked open, but Kara still knocks first because she knows how much Alex likes her privacy and she respects that. They had a rocky start, but Kara doesn’t want to ruin whatever progress they’ve made by being rude.

Alex looks up at that first knock and gives Kara a small smile. They’ve been sisters for a couple of months now and she seems to have grown on the older girl. “Hey,” Alex greets, sitting up on her bed. “What’s up? More homework questions?”

“Kind of,” Kara replies, stepping into the room, tentatively. Alex motions her further and pats the bed in front of her, offering her a place to sit. Kara smiles and accepts, folding her legs underneath her as she faces Alex. “I had health class today,” she says, “and we learned all about how babies are made.”

“Oh boy,” Alex says, turning pale. “Um, Kara, I don’t think I’m the one who should be having this talk with you…”

“I’m not asking about that,” Kara says. “Miss Mack explained it quite clearly, actually.”

“Okay…” Alex says, furrowing her brow, “then what do you want to talk about?”

“Menstruation,” Kara says, and Alex’s eyes widen. “You menstruate, don’t you?”

“Y-yes?” Alex says. “Don’t you?”

“Nope,” Kara replies. “I don’t have a uterus.”

“You don’t?”

“No. Kryptonians have different internal organs, I suppose.” Kara shrugs and opens up her notebook. “So, I know _why_ it happens—to spawn new human life—but how do humans not _die_ from all the blood loss? And why does this cause so much pain to your head and abdomen? How do you not curl up in a ball and cry?”

“Honestly?” Alex sighs. “Sometimes, I want to. My cramps get _so_ bad. But we take pills for that.”

“Like drugs?” Kara’s eyes widen, scandalously, and Alex laughs.

“Yes, like drugs,” she says. “But they’re not bad. They’re specifically made for period cramps; they dull the pain so that it’s manageable. For most people, anyway.”

Kara nods and looks down at her notebook. “How much blood do humans lose on their periods?”

Alex shrugs. “30-40 ml, give or take. Sometimes it’s as much as 80.”

“That sounds like a lot but I’m still not used to human measurements so I’ll take your word for it.” Alex chuckles. “Last question; how much do you eat on your period? I assume you would need to constantly replenish your lost blood supply.”

“Pretty much,” Alex agrees. “Well, I don’t eat as much as _you_ , but I do eat a lot. I don’t know if it’s just to replenish blood, though. I think my hormones might have something to do with it, but  I haven’t really studied human reproduction as much as I probably should.” She shrugs. “Anyway, count yourself lucky that you don’t have periods. It is the _worst_.” She falls back onto her bed and Kara crawls up to sit next to her.

“Are you menstruating right now?” she asks, with a sympathetic expression.

“Nah,” Alex sighs. “I’m PMS-ing right now, actually. My period won’t be here for another couple of months.”

Kara stares at her for a long time, after that, her eyebrows furrowed. Finally, she asks, “What’s PMS-ing?”

* * *

 

The next week, Kara’s backpack is lined with a box of tampons, pads, a bottle of Motrin, energy bars, and a heating pad. She pretends to be in pain, rubbing her abdomen during class as she takes notes and popping a couple of Motrin in clear view of a couple of her female classmates, who nod at her in empathy.

A few times, during class, she asks to be excused to the bathroom and reaches—pointedly—into her backpack and pulls out either a pad or a tampon, ‘hiding’ them in her pocket as she makes her way out of class. By the middle of the week, some of her classmates are asking her if she has any extras and Kara is all too happy to hand them over.

After all, it’s not like _she_ has any use for them. Besides that, she’s happy to help and starts making friends—albeit in probably the strangest way possible—and begins to feel like a normal girl.

All because of menstruation.

She feels a little less normal, however, when she’s watching TV with Alex—who’s on her period and resting her head in Kara’s lap while Kara strokes her hair and tries to make her feel better—when a commercial for Playtex—which Kara knows very well because that’s exactly the brand of tampons that she has sitting on the bottom of her bag—comes on and Kara frowns, her eyes widening.

“Hey, Alex?” she says.

“Hmm?” Her sister is practically a puddle in her lap, nearly completely asleep as Kara’s hands keep making gentle sweeps over her scalp.

“Why don’t you ever run up and down the beach when you’re on your period?”

“What?” Alex peeks an eye open and focuses on the television, where a 20-something year old woman is prancing down the beach in a long, flowing white sheer gown. Her arms are stretched above her head and she’s smiling, blissfully. The screen changes to an absorbency test and Kara’s hand suddenly pauses on her head.

“What’s that blue liquid?” Kara asks, looking down at Alex. “Is that what menstrual blood looks like?” Kara looks down to see Alex practically choking, tears streaming out of her eyes. “Alex? Alex, why are you laughing at me? Alex!”


End file.
